The Zero-Sum Century: Land Value, Georgism, and Why Property Tax Matters with Adam Southwick

In a role reversal, Adam Southwick — who leads delivery and statistical modeling at Valuebase — turns the mic on Will Jarvis to dig into the arguments behind Will's new book, The Zero-Sum Century. The central claim is provocative and worth sitting with: property taxes are not just a necessary evil to fund local services. They are the most fair, most pro-growth form of taxation we have, and defending them — especially the land component — may be the most consequential policy fight of the next decade.

The conversation ranges from Henry George to AI infrastructure bubbles, but the throughline is clear. Assessors sit at the center of an economic argument most people don't even know is happening. And no one is making the affirmative case for property tax loudly enough.

The Pie Stopped Growing — and That Changed Everything

Will's thesis begins with a macroeconomic observation. Since roughly 1971, productivity growth in the United States has flattened. Essential goods — housing, healthcare, education, energy — have gotten relentlessly more expensive, even as consumer electronics became basically free. When the economic pie stops growing, politics becomes zero-sum. Every policy debate turns into a knife fight over who gets a shrinking slice.

What followed were a series of one-time policy innovations to juice growth: Reagan-era tax cuts, Clinton-era globalization, the fracking revolution of the 2010s. Each bought a temporary reprieve. Each wore off. Will argues the next available lever is property tax reform — specifically, shifting more of the tax burden onto land values and away from improvements. It's an argument rooted in Henry George's insight that land, unlike capital, is inelastic. You cannot create more location. And that makes it fundamentally different from every other asset class.

What Marx and the Libertarians Both Get Wrong

One of the more striking arguments in the conversation is that both the political left and right misidentify the core economic problem. Marxists blame capital for extracting value from labor. Libertarians blame unions and regulation for constraining markets. Will contends both camps miss the real culprit: land.

He points to Thomas Piketty's Capital in the 21st Century, which argued that capital's share of wealth was growing unsustainably. But when economists decomposed Piketty's data, the gains attributed to "capital" were almost entirely driven by real estate appreciation — by land values, not corporate profits. Land is a quasi-monopoly. It doesn't behave like a competitive market. A railroad is a monopoly; so is a prime location in Manhattan. Until both sides of the political spectrum reckon with this, Will argues, we'll keep applying the wrong solutions.

The Assessor's Problem: Land Is Undervalued Systematically

This is where the conversation hits closest to home. Adam pushes Will on why assessors consistently place more value on improvements than on land, even in markets where vacant sales clearly indicate enormous locational value. The answer is a convergence of practical and political constraints.

Data on vacant land is harder to collect. There are fewer sales to train models on. Vacant land markets, especially in rural jurisdictions, are inefficient — identical lots selling at wildly different prices because an out-of-state buyer doesn't blink at the difference between $10,000 and $20,000. And then there's the political pressure. Nobody with valuable land wants to see their land assessment go up.

But the ratio studies don't lie. Vacant land is systematically underassessed in most jurisdictions. Will's prescription is straightforward: collect better data, inspect vacant parcels, and deploy statistical models — gradient-boosted trees, MRA, comparable sales approaches — that can arrive at defensible land values. The tools exist. The question is whether offices will use them.

The Florida Warning and the Little Old Lady Problem

The DeSantis push to repeal Florida's property tax and replace it with a sales tax gets sharp treatment. A sales tax is regressive — Will cites a Georgia assessor who pointed out that his $40,000-a-year front desk employee and he, at $120,000, have the same grocery bill but vastly different ability to absorb a consumption tax. It depresses economic activity. And it's trivially easy to evade across state lines. Real estate, by contrast, doesn't move.

Adam raises the most emotionally potent counterargument: the elderly homeowner on a fixed income who can't afford rising assessments. Will's response is practical. Put a lien against the property; collect when it sells. Don't restructure the entire tax system to protect one demographic at the expense of young people who already face an inverted wealth transfer — paying into Social Security, Medicare, and Medicaid for older generations while being priced out of the housing markets where good jobs exist.

AI Gains Will Flow to Landlords — Unless We Act

The conversation's most forward-looking section connects AI productivity to the Georgist framework. If the Henry George theorem holds — and a Nobel laureate confirmed it does — then the massive productivity gains from AI will be capitalized directly into real estate values in the cities where that work happens. San Francisco is already exhibit A, with houses selling $10 million over asking.

Sam Altman's original vision was explicit: fund a universal basic income through a land-based property tax. The assessment infrastructure to make that work is exactly what assessors build every day. The question is whether policy can move fast enough. As Adam dryly notes, Anthropic's infrastructure buildout might outrun the policy window.

Key Takeaway

Assessors are not just administrators of a local tax. They are the front line of the most important fiscal policy debate of the coming decade — whether the gains from AI and productivity growth will be broadly shared or silently absorbed by landowners. The tools to measure land value accurately exist. The economic theory is sound. What's missing is the political will to defend what assessors already know: location is the asset, and it should be taxed accordingly.